#include <iostream>
#include <vector>
#include <string>
#include <algorithm>

int main() {
    std::string input;
    std::getline(std::cin, input);
    std::vector<std::string> a;
    std::string temp = "";
    for (char c : input) {
        if (c == ' ') {
            a.push_back(temp);
            temp = "";
        } else {
            temp += c;
        }
    }
    a.push_back(temp);

    std::vector<char> b;
    if (a[0] == "zero") {
        b.push_back('0');
    } else if (a[0] == "one") {
        b.push_back('1');
    } else if (a[0] == "two") {
        b.push_back('2');
    } else if (a[0] == "three") {
        b.push_back('3');
    } else if (a[0] == "four") {
        b.push_back('4');
    } else if (a[0] == "five") {
        b.push_back('5');
    } else if (a[0] == "six") {
        b.push_back('6');
    } else if (a[0] == "seven") {
        b.push_back('7');
    } else if (a[0] == "eight") {
        b.push_back('8');
    } else if (a[0] == "nine") {
        b.push_back('9');
    }

    if (a[1] == "zero") {
        b.push_back('0');
    } else if (a[1] == "one") {
        b.push_back('1');
    } else if (a[1] == "two") {
        b.push_back('2');
    } else if (a[1] == "three") {
        b.push_back('3');
    } else if (a[1] == "four") {
        b.push_back('4');
    } else if (a[1] == "five") {
        b.push_back('5');
    } else if (a[1] == "six") {
        b.push_back('6');
    } else if (a[1] == "seven") {
        b.push_back('7');
    } else if (a[1] == "eight") {
        b.push_back('8');
    } else if (a[1] == "nine") {
        b.push_back('9');
    }

    if (a[2] == "zero") {
        b.push_back('0');
    } else if (a[2] == "one") {
        b.push_back('1');
    } else if (a[2] == "two") {
        b.push_back('2');
    } else if (a[2] == "three") {
        b.push_back('3');
    } else if (a[2] == "four") {
        b.push_back('4');
    } else if (a[2] == "five") {
        b.push_back('5');
    } else if (a[2] == "six") {
        b.push_back('6');
    } else if (a[2] == "seven") {
        b.push_back('7');
    } else if (a[2] == "eight") {
        b.push_back('8');
    } else if (a[2] == "nine") {
        b.push_back('9');
    }

    std::vector<int> pr = {101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307, 311, 313, 317, 331, 337, 347, 349, 353, 359, 367, 373, 379, 383, 389, 397, 401, 409, 419, 421, 431, 433, 439, 443, 449, 457, 461, 463, 467, 479, 487, 491, 499, 503, 509, 521, 523, 541, 547, 557, 563, 569, 571, 577, 587, 593, 599, 601, 607, 613, 617, 619, 631, 641, 643, 647, 653, 659, 661, 673, 677, 683, 691, 701, 709, 719, 727, 733, 739, 743, 751, 757, 761, 769, 773, 787, 797, 809, 811, 821, 823, 827, 829, 839, 853, 857, 859, 863, 877, 881, 883, 887, 907, 911, 919, 929, 937, 941, 947, 953, 967, 971, 977, 983, 991, 997};
    int y = std::stoi(std::string(b.begin(), b.end()));
    for (int i = y; i < y + 30; i++) {
        if (std::find(pr.begin(), pr.end(), i) != pr.end()) {
            std::cout << i << std::endl;
            break;
        }
    }

    return 0;
}
